In the case of a pneumatic tire, called a heavy duty tire, to be mounted on a heavy duty vehicle such as a construction vehicle, conventionally, a tread gauge, which is a thickness of a tread portion, has been increased, or a negative ratio (an area ratio of groove portions to a tread surface) of a tread pattern has been decreased, for the purpose of extending the lifetime before complete wear of a pneumatic tire.
However, the pneumatic tire called a heavy duty tire has a characteristic that a crossing width over which multiple belt layers intersect with one another is narrower than a tread contact width over which a tread surface is brought into contact with the ground. Hence, immediately before the tread surface is brought into contact with the ground, bending deformation may occur. This results in a rapid progress of wear of quarter point sections of a tread contact width (midpoints each located between a tire equator line and corresponding one of tread end contact portions on both sides).
To tackle this, a pneumatic tire has been disclosed, for which an inclination angle of belt cords constituting a belt layer to a tire equator line and the above-described crossing width are specified with respect to the quarter point sections of the tread contact width (Japanese Patent Application Publication No. 2005-297909).
In the case of the above-described conventional pneumatic tire, the wear resistance of the quarter point sections of the tread contact width is improved, and accordingly the tire lifetime is extended. However, under the current situation, further improvement in wear resistance has been demanded.
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a pneumatic tire capable of providing a greatly extended tire lifetime through great improvement in wear resistance of the quarter point sections of the tread contact width.